Less than two years after its launch, Mozilla has issued the final member of Firefox 3.0 family: version 3.0.19.

Firefox 3.0 was the center of a major effort to adopt the open-source browser. Its release in June 2008 was labeled download day, and since its release, Firefox did steadily gain in usage. Since then, though, it's been supplanted by Firefox 3.5 and now 3.6, and Mozilla decided to end the Firefox 3.0 lineage.

Accompanying the 3.0.19 release is Firefox 3.5.9, which fixes five critical security vulnerabilities. Version 3.0.19 is a relatively modest change, fixing just 13 security and stability issues

Mozilla would like people to move on from both versions, though.

"This is the last planned security and stability release for Firefox 3.0," said Mozilla's Christian Legnitto in a blog post Tuesday. "All users are encouraged to upgrade to Firefox 3.6 by downloading it from http://firefox.com/ or by selecting 'Check for Updates...' from the Help menu when using Firefox 3.5.9 or 3.0.19."